Shandong heat exchanger cleaning 2.6 material selection tube heat exchanger material should be selected according to the operating pressure, temperature and fluid corrosion. At high temperature, the mechanical properties and corrosion resistance of general materials will decline. There are few materials with heat resistance, high strength and corrosion resistance. The commonly used metal materials are carbon steel, stainless steel, low alloy steel, copper and aluminum; Non metallic materials include graphite, polytetrafluoroethylene and glass. Although stainless steel and nonferrous metals have good corrosion resistance, they are expensive and scarce, so they should be used as little as possible. The shell is made of carbon steel and the tube side is made of stainless steel. The allowable pressure drop of this design is no more than 105Pa, which can be withstood by stainless steel according to GB151-1999. 3. The determination of flow space and velocity, pipe diameter PA, refer to GB151-1999, stainless steel can bear. 3. Determination of flow space and velocity and selection of pipe diameter ф twenty-five × 2 * * cold drawn heat transfer tube (stainless steel), the flow rate in the tube is UI = 0.5m/s. 2、 = 0.5m/s. 2、 Determine the physical properties of Shandong heat exchanger cleaning data (1) qualitative temperature: take the average value of fluid inlet temperature（ The qualitative temperature of soybean oil in shell side is t = (133 + 40) / 2 = 86.5 (℃). The qualitative temperature of fluid in tube side is t = (30 + 40) / 2 = 35 ℃ (1) the qualitative temperature is the average value of fluid inlet temperature（ The qualitative temperature of soybean oil in shell side is t = (133 + 40) / 2 = 86.5 (℃). The qualitative temperature of fluid in tube side is t = (30 + 40) / 2 = 35 ℃. According to the qualitative temperature, the physical property data of fluid in shell side and tube side are obtained（ 2) The relevant physical property data of soybean oil at 90 ℃ are as follows: density: according to the qualitative temperature, the relevant physical property data of shell side and tube side fluid are checked respectively（ 2) The physical property data of soybean oil at 90 ℃ are as follows: density: ρ Shandong heat exchanger cleaning 2 kg / m3 constant pressure specific heat capacity: CPO = 2.052kj / (kg ·℃) thermal conductivity: = 2.052kj / (kg ·℃) thermal conductivity: = 2.052kj / (kg ·℃) λ O = 0.150w / (m ·℃) viscosity: = 0.150w / (m ·℃) viscosity: μ O = 0.00665 PA · s (3) physical property data of circulating cooling water at 35 ℃: density: = 0.00665 PA · s (3) physical property data of circulating cooling water at 35 ℃: density: ρ I = 993.95 kg / m3 constant pressure specific heat capacity CPI 4.174 kJ / (kg ·℃) thermal conductivity 4.174 kJ / (kg ·℃) thermal conductivity λ I = 0.6257w / (m ·℃) viscosity: = 0.6257w / (m ·℃) viscosity: μ I = 0.000728 PA · s III = 0.000728 PA · s III. total heat transfer coefficient is calculated Δ to=2000 × two point zero five two ×( 133-40)=381672 kJ/h=106.02 (kW) 2=2000 × two point zero five two ×( 133-40) = 381672 kJ / h = 106.02 (kw) 2. Average temperature difference of heat transfer: △ tmaverage temperature difference of heat transfer: △ TM '= 2121lnt TTT ∧ Δ = 30-4040-133ln30) - (40-40) - (13) Shandong heat exchanger cleaning 3 = 37.2 (℃) 3. Cooling water consumption: w = 37.2 (℃) 3. Cooling water consumption: wi = ITQ ∧ pi0c = =) / (03.9144) 3040 (174.4381672kg  4. Total heat transfer coefficient K: tube side heat transfer coefficient: 4